Different Techniques to Mitigate Partial Shading in Photovoltaic Panels

The effect of partial shading in photovoltaic (PV) panels is one of the biggest problems regarding power losses in PV systems. When the irradiance pattern throughout a PV panel is inequal, some cells with the possibility of higher power production will produce less and start to deteriorate. The objective of this research work is to present, test and discuss different techniques to help mitigate partial shading in PV panels, observing and commenting the advantages and disadvantages for different PV technologies under different operating conditions. The motivation is to contribute with research, simulation, and experimental work. Several state-of-the-artsolutions to the problem will be presented: different topologies in the interconnection of the panels; different PV system architectures, and also introducing new solution hypotheses, such as different cell interconnections topologies. Alongside, benefits and limitations will be discussed. To obtain actual results, the simulation work was conducted by creating MATLAB/Simulink models for each different technique tested, all centered around the 1M5P PV cell model. The several techniques tested will also take into account different patterns and sizes of partial shading, different PV panel technologies, different values of source irradiation, and different PV array sizes. The results will be discussed and validated by experimental tests.

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Interpretation of MPPT Techniques in Grid Connected Solar PV Array System

IJOSTHE ◽

10.24113/ojssports.v5i6.96 ◽

2019 ◽

Vol 5 (6) ◽

pp. 5

Author(s):

Neha Singh ◽

Prof. Govind Prasad Pandiya

Keyword(s):

Renewable Energy Sources ◽

Maximum Efficiency ◽

Energy Sources ◽

Solar Pv ◽

Pv System ◽

Partial Shading ◽

System Architectures ◽

Pv Systems ◽

Pv Array ◽

Uniform Condition

Solar energy is one of the most used and readily available renewable energy sources among the other energy sources. The power generated by PV systems is dependent on solar irradiance and temperature parameters. In the literature, many researchers and studies are interested in estimating true maximum efficiency point for the PV systems. Due to that fact, MPPT applications and techniques become an important issue for PV systems under both uniform and non uniform conditions. Although, PV system under uniform environment has only one maxima point on P-V curve which is simple to estimate correctly by conventional MPPT techniques, it is not as simple as under non-uniform condition such as partial shading and mismatch effects. To overcome the drawbacks of the conventional MPPTs under non uniform condition, researchers has been investigated new soft computing MPPTs, PV array configurations, system architectures and topologies.

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Design and implementation of an indoor solar emulator based low-cost autonomous data logger for PV system monitoring

International Journal of Power Electronics and Drive Systems (IJPEDS) ◽

10.11591/ijpeds.v10.i3.pp1645-1654 ◽

2019 ◽

Vol 10 (3) ◽

pp. 1645

Author(s):

Oday A. Ahmed ◽

Hussain K Sayed ◽

Kanaan A Jalal ◽

Dhari Y. Mahmood ◽

Waleed H. Habeeb

Keyword(s):

Data Acquisition ◽

Low Cost ◽

Data Acquisition System ◽

Acquisition System ◽

Renewable Energy Resources ◽

Data Logger ◽

Pv System ◽

Partial Shading ◽

Pv Systems ◽

Pv Panel

With the growing interest in renewable energy resources, a various number of studies and development for photovoltaic (PV) systems have investigated to satisfy global needs in energy. The larger interest in PV resources has increased request for suitable apparatus with which to test PV systems. This paper deals with the design of an indoor PV source emulator using an actual PV panel to facilitate PV system testing under real environment conditions. A low-cost Arduino Mega256 microcontroller-based data acquisition system (DAQ) approach has been developed to collect the data in term of voltage, power and current based on different levels of light intensity and temperature as well as under partial shading conditions. Hence, the proposed system is not just a solar emulator but it’s a complete solar emulator-DAQ system that can emulate the sunlight and monitor the PV parameters and then collect and store the data for further research investigation. The proposed monitoring system provides real time update of the solar panel characteristics at any time in the year without relying on the weather changes. This data acquisition system will be of superior interest for undergraduate and graduate students as it is both open-source and ﬂexible. The details design of the proposed PV solar emulator and data logger and its implementation are described.

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PV Systems Control Using Fuzzy Logic Controller Employing Dynamic Safety Margin under Normal and Partial Shading Conditions

Energies ◽

10.3390/en14040841 ◽

2021 ◽

Vol 14 (4) ◽

pp. 841 ◽

Cited By ~ 1

Author(s):

Mostafa Bakkar ◽

Ahmed Aboelhassan ◽

Mostafa Abdelgeliel ◽

Michael Galea

Keyword(s):

Fuzzy Logic ◽

Performance Index ◽

Safety Margin ◽

Operating Conditions ◽

Maximum Power ◽

Practical Implementation ◽

Pv System ◽

Partial Shading ◽

Pv Systems ◽

A Performance

Because of the unpredictable activity of solar energy sources, photovoltaic (PV) maximum power point tracking (MPPT) is essential to guarantee the continuous operation of electrical energy generation at optimal power levels. Several works have extensively examined the generation of the maximum power from the PV systems under normal and shading conditions. The fuzzy logic control (FLC) method is one of the effective MPPT techniques, but it needs to be adapted to work in partial shading conditions. The current paper presents the FLC-based on dynamic safety margin (DSM) as an MPPT technique for a PV system to overcome the limitations of FLC in shading conditions. The DSM is a performance index that measures the system state deviation from the normal situation. As a performance index, DSM is used to adapt the FLC controller output to rapidly reach the global maxima of the PV system. The ability of the proposed algorithm and its performance are evaluated using simulation and practical implementation results for single phase grid-connected PV system under normal and partial shading operating conditions.

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Reconfigurable Distributed Power Electronics Technique for Solar PV Systems

Electronics ◽

10.3390/electronics10091121 ◽

2021 ◽

Vol 10 (9) ◽

pp. 1121

Author(s):

Kamran Ali Khan Niazi ◽

Yongheng Yang ◽

Tamas Kerekes ◽

Dezso Sera

Keyword(s):

Energy Yield ◽

Solar Pv ◽

Charge Redistribution ◽

Pv System ◽

Partial Shading ◽

Pv Systems ◽

Simulation Based ◽

In Series ◽

A Cell ◽

Power Balancing

A reconfiguration technique using a switched-capacitor (SC)-based voltage equalizer differential power processing (DPP) concept is proposed in this paper for photovoltaic (PV) systems at a cell/subpanel/panel-level. The proposed active diffusion charge redistribution (ADCR) architecture increases the energy yield during mismatch and adds a voltage boosting capability to the PV system under no mismatch by connected the available PV cells/panels in series. The technique performs a reconfiguration by measuring the PV cell/panel voltages and their irradiances. The power balancing is achieved by charge redistribution through SC under mismatch conditions, e.g., partial shading. Moreover, PV cells/panels remain in series under no mismatch. Overall, this paper analyzes, simulates, and evaluates the effectiveness of the proposed DPP architecture through a simulation-based model prepared in PSIM. Additionally, the effectiveness is also demonstrated by comparing it with existing conventional DPP and traditional bypass diode architecture.

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A Simple Mismatch Mitigating Partial Power Processing Converter for Solar PV Modules

Energies ◽

10.3390/en14082308 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2308

Author(s):

Kamran Ali Khan Niazi ◽

Yongheng Yang ◽

Tamas Kerekes ◽

Dezso Sera

Keyword(s):

Experimental Tests ◽

Energy Yield ◽

Power Electronic ◽

Solar Pv ◽

Partial Shading ◽

Loss Analysis ◽

Pv Systems ◽

Pv Module ◽

Pv Modules ◽

In Series

Partial shading affects the energy harvested from photovoltaic (PV) modules, leading to a mismatch in PV systems and causing energy losses. For this purpose, differential power processing (DPP) converters are the emerging power electronic-based topologies used to address the mismatch issues. Normally, PV modules are connected in series and DPP converters are used to extract the power from these PV modules by only processing the fraction of power called mismatched power. In this work, a switched-capacitor-inductor (SCL)-based DPP converter is presented, which mitigates the non-ideal conditions in solar PV systems. A proposed SCL-based DPP technique utilizes a simple control strategy to extract the maximum power from the partially shaded PV modules by only processing a fraction of the power. Furthermore, an operational principle and loss analysis for the proposed converter is presented. The proposed topology is examined and compared with the traditional bypass diode technique through simulations and experimental tests. The efficiency of the proposed DPP is validated by the experiment and simulation. The results demonstrate the performance in terms of higher energy yield without bypassing the low-producing PV module by using a simple control. The results indicate that achieved efficiency is higher than 98% under severe mismatch (higher than 50%).

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An Optimized PV Control System Based on the Emperor Penguin Optimizer

Energies ◽

10.3390/en14030751 ◽

2021 ◽

Vol 14 (3) ◽

pp. 751

Author(s):

Mariam A. Sameh ◽

Mostafa I. Marei ◽

M. A. Badr ◽

Mahmoud A. Attia

Keyword(s):

Duty Cycle ◽

Optimization Technique ◽

Pso Algorithm ◽

Boost Converter ◽

Emperor Penguin ◽

Pv System ◽

Partial Shading ◽

Pv Systems ◽

Point Tracking ◽

Grid Connected Inverter

During the day, photovoltaic (PV) systems are exposed to different sunlight conditions in addition to partial shading (PS). Accordingly, maximum power point tracking (MPPT) techniques have become essential for PV systems to secure harvesting the maximum possible power from the PV modules. In this paper, optimized control is performed through the application of relatively newly developed optimization algorithms to PV systems under Partial Shading (PS) conditions. The initial value of the duty cycle of the boost converter is optimized for maximizing the amount of power extracted from the PV arrays. The emperor penguin optimizer (EPO) is proposed not only to optimize the initial setting of duty cycle but to tune the gains of controllers used for the boost converter and the grid-connected inverter of the PV system. In addition, the performance of the proposed system based on the EPO algorithm is compared with another newly developed optimization technique based on the cuttlefish algorithm (CFA). Moreover, particle swarm optimization (PSO) algorithm is used as a reference algorithm to compare results with both EPO and CFA. PSO is chosen since it is an old, well-tested, and effective algorithm. For the evaluation of performance of the proposed PV system using the proposed algorithms under different PS conditions, results are recorded and introduced.

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A Modification of the Perturb and Observe Method to Improve the Energy Harvesting of PV Systems under Partial Shading Conditions

Energies ◽

10.3390/en14092521 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2521

Author(s):

Alfredo Gil-Velasco ◽

Carlos Aguilar-Castillo

Keyword(s):

Maximum Power ◽

Global Maximum ◽

Pv System ◽

Maximum Power Point ◽

Partial Shading ◽

Pv Systems ◽

Point Tracking ◽

Power Point Tracking ◽

Power Point ◽

Computational Resources

There are multiples conditions that lead to partial shading conditions (PSC) in photovoltaic systems (PV). Under these conditions, the harvested energy decreases in the PV system. The maximum power point tracking (MPPT) controller aims to harvest the greatest amount of energy even under partial shading conditions. The simplest available MPPT algorithms fail on PSC, whereas the complex ones are effective but require high computational resources and experience in this type of systems. This paper presents a new MPPT algorithm that is simple but effective in tracking the global maximum power point even in PSC. The simulation and experimental results show excellent performance of the proposed algorithm. Additionally, a comparison with a previously proposed algorithm is presented. The comparison shows that the proposal in this paper is faster in tracking the maximum power point than complex algorithms.

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A Density Peak-Based Clustering Approach for Fault Diagnosis of Photovoltaic Arrays

International Journal of Photoenergy ◽

10.1155/2017/4903613 ◽

2017 ◽

Vol 2017 ◽

pp. 1-14 ◽

Cited By ~ 11

Author(s):

Peijie Lin ◽

Yaohai Lin ◽

Zhicong Chen ◽

Lijun Wu ◽

Lingchen Chen ◽

...

Keyword(s):

Fault Diagnosis ◽

Local Density ◽

Operating Conditions ◽

Cluster Center ◽

Pv System ◽

Density Peak ◽

Pv Systems ◽

Distribution Features ◽

Clustering Approach ◽

Distance Vector

Fault diagnosis of photovoltaic (PV) arrays plays a significant role in safe and reliable operation of PV systems. In this paper, the distribution of the PV systems’ daily operating data under different operating conditions is analyzed. The results show that the data distribution features significant nonspherical clustering, the cluster center has a relatively large distance from any points with a higher local density, and the cluster number cannot be predetermined. Based on these features, a density peak-based clustering approach is then proposed to automatically cluster the PV data. And then, a set of labeled data with various conditions are employed to compute the minimum distance vector between each cluster and the reference data. According to the distance vector, the clusters can be identified and categorized into various conditions and/or faults. Simulation results demonstrate the feasibility of the proposed method in the diagnosis of certain faults occurring in a PV array. Moreover, a 1.8 kW grid-connected PV system with6×3 PVarray is established and experimentally tested to investigate the performance of the developed method.

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Group Teaching Optimization Algorithm Based MPPT Control of PV Systems under Partial Shading and Complex Partial Shading

Electronics ◽

10.3390/electronics9111962 ◽

2020 ◽

Vol 9 (11) ◽

pp. 1962

Author(s):

Muhammad Hamza Zafar ◽

Thamraa Al-shahrani ◽

Noman Mujeeb Khan ◽

Adeel Feroz Mirza ◽

Majad Mansoor ◽

...

Keyword(s):

Particle Swarm Optimization ◽

Statistical Analysis ◽

Optimization Algorithm ◽

Maximum Power ◽

Pv System ◽

Maximum Power Point ◽

Partial Shading ◽

Swarm Optimization ◽

Pv Systems ◽

Power Point

The most cost-effective electrical energy is produced by photovoltaic (PV) systems, and with the smallest carbon footprint, making it a sustainable renewable energy. They provide an excellent alternative to the existing fossil fuel-based energy systems, while providing 4% of global electricity demand. PV system efficiency is significantly reduced by the intrinsic non-linear model, maximum power point (MPP), and partial shading (PS) effects. These two problems cause major power loss. To devise the maximum power point tracking (MPPT) control of the PV system, a novel group teaching optimization algorithm (GTOA) based controller is presented, which effectively deals with the PS and complex partial shading (CPS) conditions. Four case studies were employed that included fast-changing irradiance, PS, and CPS to test the robustness of the proposed MPPT technique. The performance of the GTOA was compared with the latest bio-inspired techniques, i.e., dragon fly optimization (DFO), cuckoo search (CS), particle swarm optimization (PSO), particle swarm optimization gravitational search (PSOGS), and conventional perturb and observe (P&O). The GTOA tracked global MPP with the highest 99.9% efficiency, while maintaining the magnitude of the oscillation <0.5 W at global maxima (GM). Moreover, 13–35% faster tracking times, and 54% settling times were achieved, compared to existing techniques. Statistical analysis was carried out to validate the robustness and effectiveness of the GTOA. Comprehensive analytical and statistical analysis solidified the superior performance of the proposed GTOA based MPPT technique.

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Improved Fractional Open Circuit Voltage MPPT Methods for PV Systems

Electronics ◽

10.3390/electronics8030321 ◽

2019 ◽

Vol 8 (3) ◽

pp. 321 ◽

Cited By ~ 11

Author(s):

Dmitry Baimel ◽

Saad Tapuchi ◽

Yoash Levron ◽

Juri Belikov

Keyword(s):

Open Circuit Voltage ◽

Open Circuit ◽

Maximum Power ◽

Pv System ◽

Maximum Power Point ◽

Pv Systems ◽

Point Tracking ◽

Pv Panel ◽

Power Point Tracking ◽

Power Point

This paper proposes two new Maximum Power Point Tracking (MPPT) methods which improve the conventional Fractional Open Circuit Voltage (FOCV) method. The main novelty is a switched semi-pilot cell that is used for measuring the open-circuit voltage. In the first method this voltage is measured on the semi-pilot cell located at the edge of PV panel. During the measurement the semi-pilot cell is disconnected from the panel by a pair of transistors, and bypassed by a diode. In the second Semi-Pilot Panel method the open circuit voltage is measured on a pilot panel in a large PV system. The proposed methods are validated using simulations and experiments. It is shown that both methods can accurately estimate the maximum power point voltage, and hence improve the system efficiency.

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